New interconnect materials: For future high reliable power module assembly

Abstract:
The trend in power electronics to move to higher operating temperatures and higher current densities has an effect on all components used inside the power module. By using different semiconductor IGBT and wire bond materials higher operating temperatures or enhanced power cycle life time can become reality. Also enhanced thermal interface materials are developed to guarantee a good thermal management during higher reliability requirements. For the chip interconnect material, standard SAC solder can be replaced by other Pb-free solder solutions using either AuSn, SnSb, Bi or Zn alloyed solders. Also Ag sinter materials - either with or without organic resin still present after sintering - or TLPS (transient liquid phase sintering) materials can be seen as possible alternatives for performing the interconnection. In this paper different interconnection materials are presented as a high reliable solution for IGBT die interconnection to cope with higher temperature requirements. Main focus will be on new developments showing Ag sintering during the die interconnection process. High dense materials with higher thermal conductivities - which either require pressure or no pressure during the sinter process - are presented.